(1) Field of the Invention
The present invention pertains to an assembly that is used to adapt a BNC type connector of a microsurgical optic fiber instrument to a threaded SMA type bushing connector of a light source.
(2) Description of the Prior Art
In microsurgery such as ophthalmic surgery or surgery of the eye, various different types of instruments are available for use by the surgeon to deliver light to the interior of the eye. These instruments deliver light for illumination as well as laser light for use in surgery. A basic microsurgical instrument of this type is comprised of a handle with a projecting tubular probe or tip and a length of optic fiber entering the rearward end of the handle and passing through the handle and the tip to the tip distal end. The proximal end of the optic fiber opposite its connection to the handle is provided with a connector for connecting the fiber proximal end to a light source, either an illumination source or a laser light source. By positioning the proximal end of the optic fiber adjacent the light source, the light is transmitted through the fiber to its distal end and is emitted from the distal end. Where the light source is a source of laser light used in eye surgery, the positioning of the fiber proximal end relative to the laser light must be accurately controlled. Connectors employed for such a purpose are referred to as SMA type connectors.
FIGS. 1 and 2 show examples of prior art SMA connectors. FIG. 1 shows the construction of a male optic fiber connector 10 and FIG. 2 shows the construction of a female optic fiber connector 12 that receives the male connector of FIG. 1. These prior art connectors are widely used and will only be described generally. The male connector 10 has a center axis 14 that is aligned coaxially with a center axis 16 of the female connector 12 when the two connectors are joined.
The female connector or bushing 12 is provided with an alignment sleeve 18 in its interior. The sleeve 18 receives the male connector 10 and ensures a precise alignment of an optic fiber (not shown) extending through the male connector 10. A laser light source is positioned relative to the female connector 12 to direct a beam of laser light along the female connector center axis 16. The female connector has a first set of external screw threading 20 that is employed in securing the female connector 12 to a wall or bracket of the laser light source to securely hold the female connector relative to the light source. A second set of external screw threading 22 on the female connector is employed in attaching the male connector 10 to the female connector 12.
The male connector 10 includes a center ferrule 24. A cable nut 26 is mounted for rotation on the center ferrule 24. The cable nut 26 is secured on the ferrule 24 by a back post 28 that is screw threaded on the ferrule. The cable nut 26 has internal screw threading 30 that is complementary to the external screw threading 22 of the female connector. The optic fiber of the microsurgical instrument (not shown) passes through the back post 28 and the ferrule 24 with a distal end of the optic fiber being positioned adjacent the distal end of the ferrule 24.
In attaching the male connector 10 to the female connector 12, the ferrule 24 is first inserted through the interior bore of the female connector and into the alignment sleeve 18. The cable nut 26 is turned causing its internal threading 30 to be screw threaded onto the external threading 22 of the female connector. This securely connects the male connector 10 with the female connector 12 with their respective axes 14, 16 aligned. In this way, the beam of laser light of the light source (not shown) is directed at the exposed end of the optic fiber contained in the male connector 10.
Use of the prior art connectors described above has been found to be inconvenient in that it is necessary to completely unscrew the cable nut 26 of the male connector 10 from the external screw threading 22 of the female connector 12 when removing one instrument from the light source, and then screw a cable nut 26 of another instrument onto the female connector external threading 22 when switching one microsurgical instrument for another. It would be more convenient if the male connector 10 could be quickly connected with and disconnected from the female connector 12 without requiring repeated rotations of a cable nut in connecting and disconnecting the two connectors.
The prior art also includes laser light sources having female connectors and sets of microsurgical instruments having male connectors that can only be used with each other. The prior art laser light source is specifically designed so that it will not operate if a male connector of a microsurgical instrument is connected to the light source, where the microsurgical instrument and male connector are not manufactured by the particular manufacturer of the light source. This is accomplished by encoding the male connector 10 of the surgical instrument with an electronic device that is recognized by the light source when the male connector is attached to the female connector of the light source. An example of such a male connector and female connector is disclosed in the U.S. Pat. No. 5,085,492 of Kelsoe et al. This has been found to be inconvenient when it is desirable to use other types of microsurgical instruments with the particular laser light source.
The above-described inconvenience could be overcome by an adapter that can be attached to the female connector of a laser light source of the type that operates only with associated electronically encoded surgical instruments where the adapter contains the electrical device recognized by the light source and also enables a quick connect and disconnect of the surgical instrument to the adapter.